PROJECT SUMMARY Alcohol use disorder (AUD) is the most common substance use disorder. Yet only a small fraction of people who need treatment receive it, and most of them get only short-term support even though continuing care has been shown to be much more effective. More consistent and available continuing care could greatly improve patient recovery. Partner support can also be critical to recovery, but many partners do not know how to support their partners' recovery or manage their own responses to it. Clinicians also lack evidence of the efforts patients are making toward recovery. Treating couples in which one member is recovering from AUD has been shown to be efficacious; in particular, Alcohol Behavioral Couples Therapy (ABCT) has shown positive outcomes. Still, ABCT has not been widely adopted, in part because of practical problems. A-CHESS is a smartphone-based system proven to substantially reduce relapse, but A-CHESS serves only the patient. Relapse prevention and recovery support for both patient and partner could be built into smartphones, which could make these services available almost anywhere and anytime. A majority of adults own a smartphone, regardless of race, education, and financial status. This project would develop and pilot test a new smartphone-based system for AUD patients, their partners, and clinicians called PartnerCHESS. PartnerCHESS would integrate key features of ABCT and A-CHESS. This R34 planning grant would pilot test PartnerCHESS and prepare for a large randomized trial to test the new system. PartnerCHESS will also include a Clinician Report that will automatically alert clinicians of patients at risk of relapse, along with other information on how recovery is proceeding. The project has three specific aims: 1. Integrate A-CHESS with key features of ABCT to create PartnerCHESS to serve patients, partners, and clinicians. 2. Conduct a pilot test (a small randomized clinical trial) of PartnerCHESS to estimate effect size and refine the protocol, procedures, recruitment strategy, measurements, and operations we would use in a large RCT. 3a. Decide whether to pursue an R01 application. 3b. Possibly plan for the R01. The project would develop PartnerCHESS with 6 recruited couples who test the system and give feedback. Once ready, the system would be tested by 34 other couples randomized to receive either PartnerCHESS + treatment as usual (TAU) or A-CHESS + TAU for a 6-month trial. Data will be collected at baseline and 2, 4, and 6 months and analyzed to see if a large clinical trial holds promise and, if so, lead to an application for support of a full-scale trial based on the elements developed and results obtained in this pilot test. The study is important to public health because of the scope of the alcohol abuse and the potential of technology to improve the lives of both patients and partners. If successful, such technology could greatly broaden the reach and impact of AUD treatment in general and couples therapy in particular.